地膜覆盖对我国干旱半干旱地区土壤温度及土壤水分的影响

Overview of the Effects of Plastic Film Mulching on Soil Temperature and Soil Moisture in Arid and Semi-arid Regions of China

地膜覆盖已经成为我国干旱半干旱地区农业生产的一项重要技术,为农业发展提供了良好的生态环境,提高了作物的产量与质量。通过对近年来有关地膜覆盖技术文献的分析和比较,综述了地膜覆盖技术在保温保墒方面的作用。地膜覆盖可为作物生长提供稳定的温度条件,在作物生育前期有良好的保温作用,保证作物的生长发育,在作物生育后期,保温作用减弱甚至可以适度降低土壤温度,使作物免受高温危害;地膜最大的保温效果是在土壤表层,随着深度增加保温效果降低;地膜颜色越浅保温效果越好。地膜覆盖可提高土壤含水量,提高作物对深层水分的利用,为作物在整个生育期内提供稳定的水分条件。生物地膜和液态地膜等新型地膜可降低对土壤的污染,起到良好的保温保墒作用。针对在地膜覆盖中存在的土壤干燥化风险加大、影响水分入渗和污染严重的问题,根据国内外研究成果,提出了加强塑料地膜替代品的研发、发展残膜的机械化回收和再利用技术、加强水分监测以及发展渗水地膜等4大措施。

Plastic film mulching has become an important agricultural technology in arid and semi-arid regions of China,providing a good ecological environment for agricultural development and improving crop yield and quality.Based on the analysis and comparison of the literature about plastic film mulch technology in recent years,the effect of plastic film mulch technology on heat preservation and moisture conservation was summarized.Plastic film mulching could provide stable temperature conditions for crop growth,and had good thermal insulation effect in the early stage of crop growth to ensure the growth and development of crops.In the late stage of crop growth,the thermal insulation effect was weakened or even could moderately reduce the soil temperature to protect crops from high temperature hazards.Mulch film had the greatest effect on the soil surface,and the effect decreased with the increase of depth.The lighter the film color was,the better the insulation effect was.Mulching with plastic film could increase soil moisture content,improve the utilization of deep water by crops,and provide stable water conditions for crops in the whole growing period.New types of mulch,such as biological mulch and liquid mulch,can reduce soil pollution and play a good role in heat preservation and moisture conservation.According to the research results at home and abroad,four measures were put forward,including strengthening the research and development of plastic film substitutes,developing mechanized recovery and reuse technology of residual film,strengthening water monitoring and developing permeable plastic film.